/**
 * Samsung One UI Design System for SchoolOS
 * Modern, clean UI following Samsung One UI design principles
 */

:root {
    /* Samsung One UI Color Palette */
    --samsung-blue: #0066FF;
    --samsung-blue-dark: #0052CC;
    --samsung-blue-light: #4D94FF;
    --samsung-blue-bg: #E6F0FF;
    
    /* Gray Scale */
    --gray-50: #FAFAFA;
    --gray-100: #F5F5F5;
    --gray-200: #EEEEEE;
    --gray-300: #E0E0E0;
    --gray-400: #BDBDBD;
    --gray-500: #9E9E9E;
    --gray-600: #757575;
    --gray-700: #616161;
    --gray-800: #424242;
    --gray-900: #212121;
    
    /* Text Colors */
    --text-primary: #212121;
    --text-secondary: #757575;
    --text-tertiary: #9E9E9E;
    --text-disabled: #BDBDBD;
    --text-white: #FFFFFF;
    
    /* Background Colors */
    --bg-primary: #FFFFFF;
    --bg-secondary: #FAFAFA;
    --bg-tertiary: #F5F5F5;
    --bg-elevated: #FFFFFF;
    
    /* Accent Colors */
    --accent-blue: #0066FF;
    --accent-green: #00C853;
    --accent-orange: #FF6D00;
    --accent-red: #D32F2F;
    --accent-purple: #7B1FA2;
    --accent-pink: #C2185B;
    --accent-teal: #0097A7;
    --accent-cyan: #00BCD4;
    
    /* Status Colors */
    --success: #00C853;
    --warning: #FF6D00;
    --danger: #D32F2F;
    --info: #0066FF;
    
    /* Shadows (Flat Design - No Shadows) */
    --shadow-xs: none;
    --shadow-sm: none;
    --shadow-md: none;
    --shadow-lg: none;
    --shadow-xl: none;
    --shadow-2xl: none;
    
    /* Border Radius (Samsung One UI - more rounded) */
    --radius-xs: 4px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-2xl: 24px;
    --radius-3xl: 28px;
    --radius-full: 9999px;
    
    /* Spacing (8px grid) */
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 20px;
    --space-6: 24px;
    --space-8: 32px;
    --space-10: 40px;
    --space-12: 48px;
    --space-16: 64px;
    --space-20: 80px;
    
    /* Typography (Samsung One UI) */
    --font-samsung: 'Samsung One', 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    --font-size-xs: 12px;
    --font-size-sm: 14px;
    --font-size-base: 16px;
    --font-size-lg: 18px;
    --font-size-xl: 20px;
    --font-size-2xl: 24px;
    --font-size-3xl: 28px;
    --font-size-4xl: 32px;
    --font-size-5xl: 40px;
    
    /* Font Weights */
    --font-weight-light: 300;
    --font-weight-regular: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* Transitions (Samsung One UI - smooth and natural) */
    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
    
    /* Elevation (Material Design influenced) */
    --elevation-0: none;
    --elevation-1: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
    --elevation-2: 0 3px 6px rgba(0, 0, 0, 0.16), 0 3px 6px rgba(0, 0, 0, 0.23);
    --elevation-3: 0 10px 20px rgba(0, 0, 0, 0.19), 0 6px 6px rgba(0, 0, 0, 0.23);
    --elevation-4: 0 15px 25px rgba(0, 0, 0, 0.2), 0 5px 10px rgba(0, 0, 0, 0.22);
    --elevation-5: 0 20px 40px rgba(0, 0, 0, 0.22), 0 8px 12px rgba(0, 0, 0, 0.24);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-samsung);
    color: var(--text-primary);
    background: var(--bg-secondary);
    line-height: 1.5;
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-regular);
    -webkit-tap-highlight-color: transparent;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: var(--font-weight-bold);
    line-height: 1.2;
    color: var(--text-primary);
    margin-bottom: var(--space-4);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-base); }

p {
    margin-bottom: var(--space-4);
    line-height: 1.6;
}

/* Samsung One UI Cards */
.samsung-card {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: none;
    border: 1px solid var(--gray-200);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.samsung-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--samsung-blue), var(--samsung-blue-light));
    opacity: 0;
    transition: opacity var(--transition-base);
}

.samsung-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--elevation-3);
}

.samsung-card:hover::before {
    opacity: 1;
}

/* Samsung One UI Buttons */
.btn-samsung {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    position: relative;
    overflow: hidden;
    min-height: 48px; /* Samsung touch target size */
}

.btn-samsung::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn-samsung:active::after {
    width: 300px;
    height: 300px;
}

.btn-samsung-primary {
    background: var(--samsung-blue);
    color: var(--text-white);
    box-shadow: none;
}

.btn-samsung-primary:hover {
    background: var(--samsung-blue-dark);
}

.btn-samsung-secondary {
    background: var(--gray-200);
    color: var(--text-primary);
}

.btn-samsung-secondary:hover {
    background: var(--gray-300);
}

.btn-samsung-success {
    background: var(--success);
    color: var(--text-white);
    box-shadow: none;
}

.btn-samsung-danger {
    background: var(--danger);
    color: var(--text-white);
    box-shadow: none;
}

/* Samsung One UI Inputs */
.input-samsung {
    width: 100%;
    padding: var(--space-4) var(--space-5);
    border: 2px solid var(--gray-300);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-base);
    font-family: var(--font-samsung);
    background: var(--bg-primary);
    color: var(--text-primary);
    transition: all var(--transition-base);
    min-height: 48px;
}

.input-samsung:focus {
    outline: none;
    border-color: var(--samsung-blue);
    box-shadow: none;
}

.input-samsung::placeholder {
    color: var(--text-tertiary);
}

/* Samsung One UI Tiles/Grid Items */
.samsung-tile {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: none;
    border: 1px solid var(--gray-200);
    transition: all var(--transition-base);
    cursor: pointer;
    position: relative;
    overflow: hidden;
    text-decoration: none;
    color: inherit;
    display: block;
}

.samsung-tile::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--samsung-blue), var(--samsung-blue-light));
    opacity: 0;
    transition: opacity var(--transition-base);
}

.samsung-tile:hover {
    border-color: var(--samsung-blue);
}

.samsung-tile:hover::before {
    opacity: 1;
}

.samsung-tile-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-4);
    font-size: 24px;
    color: var(--tile-icon-color, var(--samsung-blue));
    background: var(--tile-icon-bg, var(--samsung-blue-bg));
    box-shadow: none;
}
/* Samsung One UI - coloured icons on tiles (explicit color for reliability) */
.samsung-tile .samsung-tile-icon i,
.samsung-tile .samsung-tile-icon .fas,
.samsung-tile .samsung-tile-icon [class*="fa-"] {
    color: var(--tile-icon-color, var(--samsung-blue)) !important;
    font-weight: 400;
}
.samsung-menu-card-icon i {
    color: var(--samsung-blue);
    font-weight: 400;
}
.samsung-tile:hover .samsung-tile-icon,
.samsung-menu-card:hover .samsung-menu-card-icon {
    color: var(--tile-icon-hover, var(--samsung-blue-dark));
    background: color-mix(in srgb, var(--tile-icon-bg, var(--samsung-blue-bg)) 80%, var(--samsung-blue));
}
.samsung-tile:hover .samsung-tile-icon i,
.samsung-nav-item.active i {
    color: inherit;
}

/* Vitals stat icons - Samsung accent colours */
.vitals-stat-icon i,
.birthday-icon i {
    color: inherit;
    font-weight: 400;
}
.vitals-stat.blue .vitals-stat-icon { color: var(--samsung-blue); background: var(--samsung-blue-bg); }
.vitals-stat.green .vitals-stat-icon { color: var(--accent-green); background: rgba(0, 200, 83, 0.15); }
.vitals-stat.purple .vitals-stat-icon { color: var(--accent-purple); background: rgba(123, 31, 162, 0.15); }
.vitals-stat.red .vitals-stat-icon { color: var(--accent-red); background: rgba(211, 47, 47, 0.15); }
.vitals-stat.orange .vitals-stat-icon { color: var(--accent-orange); background: rgba(255, 109, 0, 0.15); }
.vitals-stat.teal .vitals-stat-icon { color: var(--accent-teal); background: rgba(0, 151, 167, 0.15); }

/* Tile colour variants - Samsung One UI palette */
.samsung-tile.soft-blue { --tile-icon-color: var(--samsung-blue); --tile-icon-bg: var(--samsung-blue-bg); --tile-icon-hover: var(--samsung-blue-dark); }
.samsung-tile.soft-green { --tile-icon-color: var(--accent-green); --tile-icon-bg: rgba(0, 200, 83, 0.15); --tile-icon-hover: #00A843; }
.samsung-tile.soft-purple { --tile-icon-color: var(--accent-purple); --tile-icon-bg: rgba(123, 31, 162, 0.15); --tile-icon-hover: #6B1B8E; }
.samsung-tile.soft-red { --tile-icon-color: var(--accent-red); --tile-icon-bg: rgba(211, 47, 47, 0.15); --tile-icon-hover: #B71C1C; }
.samsung-tile.soft-orange { --tile-icon-color: var(--accent-orange); --tile-icon-bg: rgba(255, 109, 0, 0.15); --tile-icon-hover: #E65100; }
.samsung-tile.soft-amber { --tile-icon-color: #FFCC00; --tile-icon-bg: rgba(255, 204, 0, 0.2); --tile-icon-hover: #FFB300; }
.samsung-tile.soft-teal { --tile-icon-color: var(--accent-teal); --tile-icon-bg: rgba(0, 151, 167, 0.15); --tile-icon-hover: #00838F; }
.samsung-tile.soft-cyan { --tile-icon-color: var(--accent-cyan); --tile-icon-bg: rgba(0, 188, 212, 0.15); --tile-icon-hover: #0097A7; }
.samsung-tile.soft-indigo { --tile-icon-color: #5856D6; --tile-icon-bg: rgba(88, 86, 214, 0.15); --tile-icon-hover: #4741C4; }
.samsung-tile.soft-pink { --tile-icon-color: var(--accent-pink); --tile-icon-bg: rgba(194, 24, 91, 0.15); --tile-icon-hover: #AD1457; }
.samsung-tile.soft-yellow { --tile-icon-color: #FFCC00; --tile-icon-bg: rgba(255, 204, 0, 0.2); --tile-icon-hover: #FFB300; }
.samsung-tile.soft-gold { --tile-icon-color: #FFB300; --tile-icon-bg: rgba(255, 179, 0, 0.2); --tile-icon-hover: #FF8F00; }
.samsung-tile.soft-mint { --tile-icon-color: #00C7BE; --tile-icon-bg: rgba(0, 199, 190, 0.15); --tile-icon-hover: #00A39B; }

.samsung-nav-item i {
    color: var(--text-secondary);
    opacity: 0.85;
}
.samsung-nav-item.active i {
    color: var(--samsung-blue);
    opacity: 1;
}

.samsung-tile-label {
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    color: var(--text-primary);
    margin-bottom: var(--space-2);
}

.samsung-tile-value {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--text-primary);
}

.samsung-tile-sublabel {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-top: var(--space-1);
}

/* Samsung One UI Header */
.samsung-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 64px;
    background: var(--bg-primary);
    box-shadow: none;
    border-bottom: 1px solid var(--gray-200);
    z-index: 1000;
    display: flex;
    align-items: center;
    padding: 0 var(--space-6);
}

.samsung-header-title {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

/* Samsung One UI Grid */
.samsung-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: var(--space-4);
    padding: var(--space-6);
}

@media (max-width: 768px) {
    .samsung-grid {
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
        gap: var(--space-3);
        padding: var(--space-4);
    }
}

/* Samsung One UI Menu Cards */
.samsung-menu-card {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: none;
    border: 1px solid var(--gray-200);
    text-decoration: none;
    color: inherit;
    display: block;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.samsung-menu-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--samsung-blue), var(--samsung-blue-light));
    opacity: 0;
    transition: opacity var(--transition-base);
}

.samsung-menu-card:hover {
    border-color: var(--samsung-blue);
}

.samsung-menu-card:hover::before {
    opacity: 1;
}

.samsung-menu-card-icon {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-4);
    font-size: 28px;
    color: var(--samsung-blue);
    background: var(--samsung-blue-bg);
    box-shadow: none;
}

.samsung-menu-card h3 {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--space-2);
    color: var(--text-primary);
}

.samsung-menu-card p {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    line-height: 1.5;
    margin-bottom: 0;
}

/* Samsung One UI Badge */
.samsung-badge {
    display: inline-flex;
    align-items: center;
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    background: var(--samsung-blue-bg);
    color: var(--samsung-blue);
}

/* Samsung One UI Container */
.samsung-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-6);
}

/* Samsung One UI Section Header */
.samsung-section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-6);
    padding-bottom: var(--space-4);
    border-bottom: 2px solid var(--gray-200);
}

.samsung-section-title {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

/* Ripple Effect */
@keyframes ripple {
    0% {
        transform: scale(0);
        opacity: 1;
    }
    100% {
        transform: scale(4);
        opacity: 0;
    }
}

.ripple {
    position: relative;
    overflow: hidden;
}

.ripple::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.ripple:active::after {
    width: 300px;
    height: 300px;
    animation: ripple 0.6s ease-out;
}

/* Responsive */
@media (max-width: 480px) {
    .samsung-container {
        padding: var(--space-3);
    }
    
    .samsung-menu-card {
        padding: var(--space-4);
    }
    
    .samsung-tile {
        padding: var(--space-4);
        min-height: 100px;
    }
    
    .samsung-tile-icon {
        width: 48px;
        height: 48px;
        font-size: 24px;
    }
    
    .samsung-tile-value {
        font-size: var(--font-size-2xl);
    }
    
    .samsung-tile-label {
        font-size: var(--font-size-sm);
    }
    
    .samsung-section-title {
        font-size: var(--font-size-xl);
    }
    
    .dashboard-header {
        padding: var(--space-4);
    }
    
    .welcome-section {
        flex-direction: column;
        align-items: flex-start;
    }
}

@media (min-width: 481px) and (max-width: 767px) {
    .samsung-container {
        padding: var(--space-4);
    }
    
    .samsung-menu-card {
        padding: var(--space-5);
    }
    
    .samsung-tile {
        padding: var(--space-5);
    }
}

@media (min-width: 768px) and (max-width: 1023px) {
    .samsung-container {
        padding: var(--space-5);
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .stats-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 1440px) {
    .stats-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* Utility Classes */
.text-samsung-primary { color: var(--samsung-blue); }
.bg-samsung-primary { background: var(--samsung-blue); }
.bg-samsung-gradient {
    background: linear-gradient(135deg, var(--samsung-blue), var(--samsung-blue-light));
}